Abstract: A tire vulcanization mold in which a surface roughness in the groove molding portion of the tread molding surface is made smaller than a surface roughness in the land portion molding portion, in which a surface roughness in the groove molding portion is minimized to 0.12 ?m or less in a range including at least a main groove molding portion, and in which a surface roughness in the land portion molding portion is made to be 3.2 ?m or more, is used to manufacture a tire, and when cleaning the tread molding surface, the tread molding surface is irradiated with a laser beam to remove contaminant adhered to the tread molding surface.

Abstract: A tire vulcanization mold in which a surface roughness in the groove molding portion of the tread molding surface is made smaller than a surface roughness in the land portion molding portion, in which a surface roughness in the groove molding portion is minimized to 0.12 ?m or less in a range including at least a main groove molding portion, and in which a surface roughness in the land portion molding portion is made to be 3.2 ?m or more, is used to manufacture a tire, and when cleaning the tread molding surface, the tread molding surface is irradiated with a laser beam to remove contaminant adhered to the tread molding surface.

Abstract: The rubber composition of the present technology comprises: from 35 to 50 parts by weight of silica, from 1.5 to 3.5 parts by weight of sulfur, carbon black, a sulfenamide vulcanization accelerator, and a sulfur-containing silane coupling agent per 100 parts by weight of a diene rubber containing from 80 to 100 wt. % of a natural rubber; a total amount of the sulfur and the sulfur in the sulfur-containing silane coupling agent being from 1.85 to 6.0 parts by weight; and a compounded amount of the sulfenamide vulcanization accelerator being from A parts by weight to 2.6 parts by weight both inclusive, where A is determined by the formula A=0.2209S2?1.409S+1.309Y+2.579, where S is the compounded amount of the sulfur and Y is a positive number.